Should have been the headline: “UK Intelligence Services fail miserably again”. After spending billions of pounds on intelligence services, the services could not discover a bomb network plot right under their noses but could spy on Trump in the US and have its current and former queer, freak, pervert, traitor and incompetent “intelligence experts” fabricate fake dossiers.
If you look dispassionately at the record (and I know it's difficult to be dispassionate when something like this happens), the UK security forces have had far more successes than failures in dealing with Muslim terrorism over the last decade. In that period there have been three 'successful' terrorist attacks (ie resulting in fatalities): the Lee Rigby killing, the Westminster Bridge attack earlier this year, and now this. Manchester was the first such attack anywhere in the UK outside London.
Meanwhile, in the last 3 years alone, there have been over 90 convictions for conspiracy to commit acts of terrorism - in other words potential attacks which were foiled by security before they could happen.
That's not a bad record in the circumstances.